strcat giving a stack smashing detected error

ashlesha · 03-11-2007, 10:43 AM

Hi,

This is my program:

Quote:

#include<stdio.h>

#include<stdlib.h>

#include<strings.h>

#include<string.h>

void itoa (int n, char s[]);
void reverse (char s[]);

int main()
{
char ash[20],chi[20],temp[40];
int a,b,taxi_state,count,error[11]={1,2,3,4,5,6,7,8,9,0,11};

count=-1;
while(count<10)
{
itoa(error[count++],temp);
strcat(ash,temp);
}

printf("%s\n",ash);
return 0;
}

Anytime I have the strcat function, I get the following error by gcc:

Quote:

*** stack smashing detected ***: ./test2 terminated
Aborted (core dumped)

What does this error mean exactly?

Thanks,
Ashlesha.

Using UBUNTU 6.1

random0 · 03-11-2007, 11:02 AM

You are getting that error because your system detects an attempt at a buffer overflow attack in your program. In your particular case, the temp buffer is larger than the ash buffer and trying to strcat temp onto ash writes out of the bounds of ash; that is what your system is detecting. You could modify temp to be smaller or you could read the man page on strcat for further advice.

ashlesha · 03-11-2007, 11:15 AM

Thank you --

yeah it works now -- the problem was that the source buffer must be a const
so i just said temp[0]=0; and it works

-Ashlesha